High temperature oxidation behavior of Ti3SiC2-based material in air

The oxidation behavior of Ti3SiC2-based material in air has been studied from 900 degreesC to 1200 degreesC. The present work showed that the growth of the oxide scale on Ti3SiC2-based material obeyed a parabolic law from 900 degreesC to 1100 degreesC, while at 1200 degreesC it followed a linear rule. The oxide scale was generally composed of an outer layer of coarse-grained TiO2 (rutile) and an inner layer of fine-grained TiO2 and SiO2 (tridymite) above 1000 degreesC, A discontinuous coarse-grained SiO2 layer was observed within the outer coarse-grained TiO2 layer on the samples oxidized at 1100 degreesC and 1200 degreesC. Marker experiments showed that the oxidation process was controlled by the inward diffusion of oxygen. outward diffusion of titanium and CO or SiO, and that internal oxidation predominated. The TiC content in Ti3SiC2 was deleterious to the oxidation resistance of Ti3SiC2. (C) 2001 Acta Materialia Inc. published by Elsevier Science Ltd. All rights reserved.